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Rheiformes

plural noun
Rhe·​ifor·​mes | \ ˌrēəˈfȯr(ˌ)mēz\

Definition of Rheiformes

: an order of birds that are intermediate in some respects between the ostriches and the emus and cassowaries and that comprise the recent and extinct rheas

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History and Etymology for Rheiformes

New Latin, from Rhea + -iformes

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